During the processing or storage of waste, for instance industrial waste such as soil and fly ash, the waste may be concentrated into piles. When waste is concentrated into piles, it is often necessary to cover the waste piles to minimize the emission of odor and prevent the movement of the waste, particularly when the waste is particulate.
Several spray-on coatings have been developed to provide an effective cover to waste piles. These include the coatings described in U.S. Pat. Nos. 5,161,915; 5,275,508; 5,385,429; 5,525,009; and 7,544,243 (the disclosures of which are incorporated by reference here in their entirety), which are marketed under the registered trademark POSI-SHELL by LSC Environmental Products, LLC of Apalachin, N.Y. These cover materials typically comprise a mixture of water, mineral binder (such as cement kiln dust, “CKD,” or similar materials), and fibers (both cellulose and synthetic) that can be sprayed on to a waste pile and allowed to set to provide an effective cover. These mineral-based covers have proven to provide effective covers to landfills and other waste piles.
Other prior art cover materials, for example, those described in U.S. Pat. Nos. 5,082,500 and 5,516,830, are primarily fiber based. These fiber based cover materials also include clay and a polymer that aid in retaining the integrity of the fiber-based matrix. These prior art covers are predominantly fiber with minor amounts of clay binder. Since the fiber in the fiber-based covers tends to agglomerate or flocculate, it is inherently difficult to fluidize the fiber based slurry in order to pump and spay these fiber-containing products effectively. Accordingly, these fiber-based cover materials typically require inordinately large water content to prevent agglomeration of the fibers. However, the low solids content of such fiber-based cover materials provides a non-uniform cover that, when subjected to rain and wind, can lose its integrity.
Aspects of the present invention overcome these and other limitations of the prior art and provide an effective bulk material pile cover that can be easily applied and maintained without the limitations and disadvantages of prior art material cover materials. Aspects of the present invention provide improved adhesion and ease in application, in that the spray can be applied quickly and easily.